1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2021 Facebook */ 3 #include "vmlinux.h" 4 #include <bpf/bpf_helpers.h> 5 #define vm_flags vm_start 6 7 char _license[] SEC("license") = "GPL"; 8 9 struct callback_ctx { 10 int dummy; 11 }; 12 13 static long write_vma(struct task_struct *task, struct vm_area_struct *vma, 14 struct callback_ctx *data) 15 { 16 /* writing to vma, which is illegal */ 17 vma->vm_flags |= 0x55; 18 19 return 0; 20 } 21 22 SEC("raw_tp/sys_enter") 23 int handle_getpid(void) 24 { 25 struct task_struct *task = bpf_get_current_task_btf(); 26 struct callback_ctx data = {}; 27 28 bpf_find_vma(task, 0, write_vma, &data, 0); 29 return 0; 30 } 31